| 摘要 |
<p>589,023. Wireless transmitting and receiving apparatus ; discharge appasatus. COOKE, A. H., SKINNER, H. W. B., WARD, A. G., and WRIGHT, C. S. March 9, 1942, No. 3056. [Classes 39 (i) and 40 (v)] A device for the control of high-frequency power comprises a cavity resonator, having input and output couplings to a transmission line or wave guide and enclosed partly or wholly within a gas-filled tube which on the occurrence of a glow discharge damps the resonator and thus reduces the flow of energy along the line or guide. The device may be used in a combined radio transmitter and receiver, such as a radio location apparatus, for protecting the receiving apparatus from the high voltage pulses present in the transmitter. As shown, the resonator is formed by sealing copper plates 20, formed for example as in Specification 589,022, between sections of glass tubing 16, the plates being bent towards each other to form the circular poles 3 of the resonator, and their outer edges being clamped outside the tube to a silvered metal ring 17. Radial apertures are formed in this ring to receive tuning plungers and to form connections for input and output transmission lines 23, 23<1>, the inner members of which are extended to form adjustable coupling loops 24, 24'. When used as a protective device, high voltages on the input side cause a discharge at the poles 3 and thus damp the resonator and prevent damage to apparatus on the output side. The glow discharge may be excited by an external control applied to an electrode such as 25 placed axially in the tube 16 and terminating in an insulating tube close to the poles 3. To minimize time 'lag at the commencement of the discharge, a steady discharge may be passed between the outside of the resonator and one or more auxiliary electrodes within the tube, and ionization may be produced by a deposit of mesothorium or radium compounds on an auxiliary electrode or on the resonator surface near the poles ; or photo electrons may be produced by a luminous source shining into the tube. The tube filling may comprise water vapour at a pressure of 3 to 10 mm. of mercury, water vapour mixed with one or more gases such as hydrogen or helium, alcohol or other organic vapour, hydrochloric acid, or ammonia. When wave guides are used for the input or output energy, the guide opens directly into the resonator through a suitable aperture.</p> |
